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To strengthen waterborne polyurethane/polyvinyl alcohol nanofibers which is a potential filtering material, in this work, modified graphene oxide (GO) was mixed into the solution of waterborne polyurethane and polyvinyl alcohol. By electrospinning, the modified GO/waterborne polyurethane/polyvinyl alcohol nanofibers were prepared. The composite nanofibers showed good thermal behavior due to the addition of modified GO. The results show that the maximum thermal decomposition temperature of nanofibers film increased by 26 °C when the content of modified GO was 0.4% in the composite nanofiber. At the same time, the tensile property of the composite nanofiber was improved and a better mechanical behavior appeared when using a rotating way to fabricate the nanofibers, which the value of tensile length at break in the radial direction and tensile strength at break in arc direction rose by 68.7% and 38.7% separately. [ABSTRACT FROM AUTHOR]

Conductive fibers are widely used in coatings and related applications. An effective production method is important. In this work, reduced graphene oxide (rGO) was added into the solution of poly(3,4-ethylenedioxythiophene) (PEDOT), poly(styrenesulfonate) (PSS) and polyvinyl alcohol (PVA). The rGO/PEDOT: PSS/PVA conductive nanofibers were prepared by electrospinning using a high-speed horizontal rotating collector instead of a traditional plane collector. The thermal behavior of composite nanofibers with rGO showed good stability compared with PEDOT: PSS/PVA nanofibers. The results show that the conductivity of nanofibers film was enhanced significantly by 100% when the content of 0.2% rGO in the PEDOT: PSS/PVA nanofiber. Further increase of rGO component content resulted in a limited increase in conductivity but with a sharp decline of the mechanical properties of the fibers. The tensile property of the nanofibers gained a significant improvement by 46.9% and 66.5% in the arc and radial direction, which indicates that high-speed horizontal rotating reception can make the texture more regular and stronger in the process of electrospinning. [ABSTRACT FROM AUTHOR]

Background: BRCA2 mutation has a more substantial impact on the homologous recombination and superior therapeutic response to platinum-based chemotherapy than BRCA1 mutation. Whether BRCA2-mutated patients could benefit more from PARPi than BRCA1-mutated patients remains unclear. We performed a meta-analysis to assess the efficacy difference of PARPi between BRCA1 mutation carriers and BRCA2 mutation carriers. Methods: Pubmed, Embase, and Cochrane Library were comprehensively searched for randomized controlled trials (RCTs) of PARPi that had available hazard ratios (HRs) of progression-free survival (PFS) in both BRCA1-mutated population and BRCA2-mutated population. We calculated the pooled PFS HRs and 95%CI using randomized-effect models, and the difference between the two estimates was compared by interaction test. Results: A total of 11 eligible RCTs of high quality were identified through search. Overall, 1544 BRCA1 mutation carriers and 1191 BRCA2 mutation carriers were included in the final analysis. The pooled PFS HR was 0.42 (95% CI: 0.35-0.50) in BRCA1-mutated patients who were treated with PARPi compared with patients in the control group. In BRCA2-mutated patients treated with PARPi, the pooled PFS HR compared with the control groups was 0.35 (95% CI: 0.24-0.51). The difference in efficacy of PARPi was not significant between the two subgroups (P heterogeneity = 0.40, for interaction). Conclusion: BRCA1-mutated patients and BRCA2-mutated patients could benefit from PARPi, and the efficacy is comparable. Currently, there is no evidence that BRCA2-mutated patients would benefit more from PARPi than BRCA1-mutated patients. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/ , identifier CRD42020214582. [ABSTRACT FROM AUTHOR]

TiO2/WPU/PVA nanofibers were prepared by electrospinning with modified nano-TiO2, waterborne polyurethane (WPU) and polyvinyl alcohol (PVA) as main materials that were blended mechanically. The nanofibers morphologies and physical states were investigated using scanning electron microscopy (SEM), thermogravimetry analysis (TG), Fourier transform infrared (FTIR) spectroscopy and UV-visible (UV-Vis) spectroscopy. Scanning electron microscopy observations revealed that nano-TiO2 was modified by r-aminopropyltriethoxysilanehe in order to improve the dispersion of nano-TiO2 in WPU/PVA matrix and the spinning quality of composite fibers was improved by adding proper amount of modified nano-TiO2. When the content of modified nano-TiO2 was 1%, the composite fibers with uniform diameter distribution were obtained. Results from FTIR and TG suggested that modified nano-TiO2 had been successfully introduced to the WPU/PVA nanofibers and TiO2/WPU/PVA nanofibers had the best thermal stability when the content of modified nano-TiO2 was 1%. Results from UV-Vis suggested that the photocatalytic performance of composite nanofibers that degraded methyl orange was enhanced by the addition of modified nano-TiO2. [ABSTRACT FROM AUTHOR]

Nano-TiO2/poly(methylmethacrylate) nanofibres were prepared by electrospinning with poly(methylmethacrylate) (PMMA) and anatase nano-TiO2 as main materials which were blended mechanically and dissolved in dimethylformamide (DMF) and ethyl ethanoate (EA) solvent. The nanofibres morphologies and physical states were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetry analysis (TG), fourier transform infrared (FTIR) spectroscopy and UV–visible (UV–Vis) spectroscopy. Scanning electron microscopy observations revealed that when the content of TiO2 was 5%, nano-TiO2/poly(methylmethacrylate) nanofibres had the minimum average diameter which was 409 nm. Results from FTIR, XRD and TG suggested that anatase nano-TiO2 had been successfully introduced to the PMMA matrix and TiO2/PMMA nanofibres had good thermal stability within 300 °C. Results from UV–Vis suggested that when 10% of anatase nano-TiO2 was added, the photocatalytic decomposition of methyl orange was 50% higher than that of pure PMMA nanofibres under sunlight irradiation for 5 h. [ABSTRACT FROM AUTHOR]

R-TiO2/PMMA nanofibers were prepared by electrospinning with poly(methylmethacrylate) (PMMA) and rutile nano-TiO2 (R-TiO2) as main materials which were blended mechanically, and dimethylformamide (DMF) and ethyl ethanoate (EA) as component solvent. The nanofibers morphologies and physical states were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetry analysis (TG), fourier transform infrared (FTIR) spectroscopy and UV-visible (UV-Vis) spectroscopy. Scanning electron microscopy observations revealed that with the increase of DMF proportion in solvent the fibers average diameter gradually decreased, with the increase of EA ratio in solvent more micropores emerged, and as the content of R-TiO2 increased, the fibers average diameter decreased initially, then followed by an increase. When the content of R-TiO2 was 5%, the minimum fibers average diameter was 436 nm. Results from FTIR, XRD and TG suggested that rutile nano-TiO2 had been successfully introduced to the PMMA matrix and R-TiO2/PMMA nanofibers had good thermal stability, and heating weightlessness was less than 2% in the 300 °C. Results from UV-Vis suggested that when 10% of rutile nano-TiO2 was added, the degradation of methyl orange was 30% higher than that of pure PMMA nanofibers under sunlight irradiation. [ABSTRACT FROM AUTHOR]

Simethicone MMT/PU microspheres were prepared with polyurethane (PU) and montmorillonite (MMT) as main materials by interfacial polymerization and simethicone as core material was coated into microspheres. The microspheres morphologies and composite physical states were investigated using scanning electron microscopy (SEM), thermogravimetry analysis (TG), fourier transform infrared (FTIR) spectroscopy and dynamic thermomechanical analysis (DMA). Scanning electron microscopy observations revealed that simethicone MMT/PU microspheres had a good spherical structure. Results from FTIR and TG suggested that the MMT had been successfully introduced to the polyurethane molecular chain and simethicone MMT/PU microspheres had good thermal stability under 225°C. Results from DMA suggested that damping properties of simethicone MMT/PU/EP composites were significantly improved. As simethicone MMT/PU microspheres were introduced into epoxy resin (EP), the maximum loss factor of simethicone/MMT/PU/EP composites increased by 90% than pure EP. [ABSTRACT FROM AUTHOR]

PVA/P(AA-AM) super absorbent polymer was prepared with polyvinyl alcohol (PVA), acrylic acid (AA) and acrylamide (AM) as main materials by solution polymerization. The morphologies and composite physical states were investigated using fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetry analysis (TG-DTG). Scanning electron microscopy observations revealed that a large number of porous network structures existed in the resin. Results from FTIR and XRD suggested that PVA/P(AA-AM) superabsorbent which had semi-interpenetrating network structure had been successfully prepared. Results from TG-DTG suggested that PVA/P(AA-AM) superabsorbent had good thermal stability under 200°C. At the same time it had good water retention property and the water retention property of sandy soil was improved obviously when the resin was added into the sandy soil. [ABSTRACT FROM PUBLISHER]

By electronspinning PLA/NCC nanofibers were prepared with polylactic acid (PLA) and nanocellulose whiskers (NCC) which obtained from microcrystalline cellulose (MCC) by sulfuric acid hydrolysis. The morphologies and physical states were investigated using scanning electron microscopy (SEM), thermogravimetric analysis (TG-DTG) and differential scanning calorimetry (DSC). When the mass fraction of NCC was 5%, scanning electron microscopy observations revealed that the diameter of PLA/NCC nanofibers was the smallest and the distribution was uniform and results from TG-DTG and DSC suggested that thermal decomposition temperature of composite films was approximately increased by 20°C than pure PLA film, at the same time mechanical and hydrolysis property of composite films were obviously improved. [ABSTRACT FROM PUBLISHER]

In this paper, fiber-tourmaline was for the first time used in preparation of fiber tourmaline nano powder. The preparation process of fiber tourmaline/PVA spinning solution based on the vinyl acetate, fiber tourmaline nano powder and EDTA was described through the use of micro-polymer chemistry laboratory equipment. The utilization of micro-polymer processing equipment-electrostatic spinning machine for the first time successfully prepared the fiber tourmaline/PVA composite nanofibers. The samples were characterized and the performance of its anion was tested, after which the impact of the addition of fiber tourmaline upon the electrospun fiber was analyzed and the best quality scores of tourmaline that need were also discussed. [ABSTRACT FROM AUTHOR]

P(U-MMA-ANI) interpenetrating polymer network (IPN) damping and absorbing material is successfully synthesized by PANI particles served as an absorbing agent with the microemulsion polymerization and P(U-MMA) foam IPN network structure for substrate materials with foaming way. P(U-MMA-ANI) IPN is characterized by the compression mechanical performance testing, TG-DSC, and DSC. The results verify that the P(U-MMA) IPN foam damping material has a good compressive strength and compaction cycle property, and the optimum content of PMMA was 40% (mass) with which the SEM graphs do not present the phase separation on the macro level between PMMA and PU, while the phase separation was observed on the micro level. The DTG curve indicates that because of the formation of P(U-MMA) IPN, the decomposition temperature of PMMA and the carbamate in PU increases, while that of the polyol segment in PU has almost no change. P(U-MMA-ANI) IPN foam damping and absorbing material is obtained by PANI particles served as absorbing agent in the form of filler, and PMMA in the form of micro area in substrate material. When the content of PANI was up to 2.0% (mass), the dissipation factor of composites increased, and with the increasing of frequency the dissipation factor increased in a straight line.